The Insanity Defense before 1800

The earliest context in which madness is treated as an excuse for crime is Justinian's Digest. The Christian church brought this feature of Roman law to pre-Norman England. Madmen were probably not regarded as triable by ordeal, but were simply left to be guarded by their kinsfolk. When trial by ordeal was abandoned, and juries had to determine guilt, juries were at first expected to find madmen guilty but refer their cases to the king for pardon. It was not until about 1500 that juries seem to have begun to acquit on grounds of insanity. The reasoning varied: madmen were “punished enough by their madness†; they “lacked the will to harm†; they could not “tell good from evil.†How strictly the tests of insanity were applied depended on the crime. The rejections of the defense that figured in the State Trials series were not typical, but gave historians the impression that the defense hardly ever succeeded before Hadfield's trial in 1800. In fact, as the Old Bailey Sessions Papers show, it often succeeded in the eighteenth century. Nor was this the result of empire building by the medical professions. Laymen's evidence was often accepted without any testimony by mad-doctors.